“Finite Time Blowup for Navier–Stokes” A core question in fluid dynamics is whether a perfectly smooth 3D flow can develop infinite velocity in finite time, and it's important enough that it's one of the seven Millennium Prize Problems. This paper from OpenAI constructs a vortex that spins faster and faster while collapsing into an increasingly tiny region, so velocity blows up even though total kinetic energy stays bounded. Their trick is adding tiny oscillatory flows that extract energy…